title: Viability and function of human sperm in electrolyte-free cold preservation.
abstract: OBJECTIVE
  To assess the viability and function of human sperm in electrolyte-free cold preservation.
  
  
  METHODS
  Prospective comparative study.
  
  
  METHODS
  Andrology laboratory of our hospital.
  
  
  METHODS
  Ten semen samples obtained from patients attending our infertility clinic.
  
  
  METHODS
  Ejaculated sperm were washed using the electrolyte-free Percoll gradient and were then preserved in 0.33 M glucose solution, 0.16 M NaCl solution, 0.16 M KCl solution at 4 degrees C for 4 weeks. As a control, TEST (TES and Tris) yolk buffer (TYB) was added to the ejaculated semen and preserved at 4 degrees C.
  
  
  METHODS
  Sperm tail morphology, motility, viability (eosin-Y stain), and the concentration of adenosine triphosphate (ATP) were analyzed.
  
  
  RESULTS
  The number of sperm with normal tail form and the motility of sperm preserved in glucose solution (electrolyte-free cold preservation) were significantly (P < 0.01) higher for 4 weeks than those of sperm preserved in the other three media. The sperm viability in glucose solution was 75.5%, 65.4%, and 51.3%, after 1, 2, and 4 weeks, respectively. The ATP concentration after 1, 2, and 4 weeks remained 64.2%, 53.0%, and 4.3% of the prestorage value, respectively, in the sperm stored in glucose solution.
  
  
  CONCLUSIONS
  The morphology, motility, viability, and ATP concentration of sperm in electrolyte-free cold preservation were substantially better than those in NaCl solution, KCl solution, or TYB for 2 weeks.
authors.affiliation: Department of Urology, Yokohama City University School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kanno
authors.forename: K
authors.initials: K
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Ogawa
authors.forename: M
authors.initials: M
authors.lastname: Takeda
authors.forename: A
authors.initials: A
authors.lastname: Iwasaki
authors.forename: Y
authors.initials: Y
authors.lastname: Kinoshita
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D002470:Cell Survival; D015925:Cryopreservation; D004573:Electrolytes / Q000494:pharmacology; D004801:Eosine Yellowish-(YS); D005456:Fluorescent Dyes; D006801:Humans; D008297:Male; D009994:Osmolar Concentration; D011446:Prospective Studies; D012662:Semen Preservation; D013081:Sperm Motility / Q000502:physiology; D013082:Sperm Tail / Q000648:ultrastructure; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism / Q000502:physiology*
chemical_list: D004573:Electrolytes; D005456:Fluorescent Dyes; D000255:Adenosine Triphosphate; D004801:Eosine Yellowish-(YS)